Insecticidal composition comprising nicotine sulfate and 4, 4&#39;-dichlorodiphenyl sulfide



Patented Oct. 30, 1951 INSECTIOIDAL COMPOSITION COMPRISING NICOTINE SULFATE AND 4,4'-DICHLORO- DIPHENYL SULFIDE Charles F. Woodward, Abington, Pa., and Elmer L. Mayer, Yorba Linda, Calif., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Application February 18, 1949,

Serial No. 77,266

2 Claims. on. 167-30) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described, if patented in any country, may be manufactured and used by or for the Government of the United States of America for governmental purposes throughout the world without the payment to us of any royalty thereon.

This invention relates to insecticides. It particularly relates to synergistic additaments for nicotine, nicotine salts, and other nicotine complexes and compounds, which make it possible to attain the same or higher degree of toxicity with substantially smaller amounts of active ingredients.

We have found that synergistic insecticidal action results when insecticidal compounds are used in conjunction with aromatic sulfides as synergists therefor. Thus, synergistic insecticidal action results when an insecticidal composition containing nicotine or a nicotine compound as an active ingredient is used in conjunction with'an organic sulfide in which the sulfur atom is linked to identical or to'different aromatic hydrocarbon radicals fre from substituents other than halogen. Suitable aromatic sulfides include for instance compounds corresponding to the general formula:

wherein R. and R are alkyl radicals, or halogen, for example, chlorine or bromine and X and Y each represent zero or a small integer such as, 1, 2, 3, 4, or 5.

This inventio is illustrated by the following tabulated expe imental data obtained by using insecticidal compositions comprising nicotine sulfate, as an example of an insecticidal agent, and 4,4 dichlorodiphenyl sulfide (4,4' dichlorodiphenyl thio ether) as a synergist therefor, incorporated in an inert dust, as an illustrative carrier for these active ingredients. These data also include tests made by employing dust compositions containing nicotine sulfate alone and also containing 4,4-dichlorodiphenyl sulfide alone. The tests were conducted on the third instar larvae of the diamondback moth by methods similar to those described by Swingle (Laboratory procedures in studies of the chemical control of insects, Am. Assoc. Adv. Sci. 20, 82-84 [1943]).

The individual insecticidal effects of nicotine sulfate and of 4,4'-dichlorodiphenyl sulfide, at various concentrations, are shown in Table I, following:

Table I 4.4-Dichlorodiphenyl Nicotine Sulfate Sulfide Concentra- Concentration, mlCI'O- Average tion, micro- Average grams per mortality, grams per mortality, square centiper cent square centiper cent meter meter The results obtained using compositions containing nicotine sulfate in admixture with 4,4-

5 dichlorophenyl sulfide are shown in Table II, 1'01- lowing:

Table II Concentration of Active Ingredients, micrograms persquarecentimeter Average Mortality 1.1 nicotine sulfate+l.1. 2.2 nicotine sulfate+2.2. 3.0 nicotine Sulfate+3.0

4,4diichlorodiphenyl sulfideo -do from separate, actions of the two insecticidal agents, are indicated in Table 111, following:

1 Calculated on the basis oi e 0.22 nicotine equivalent for 4,4- dIiJchll)oi-od)iphenyl sulfide at the dosage giving 50 percent mortality .50

Analogous results showing a pronounced synergistic action were obtained when various insecticidal compositions containing mixtures of nicotine, or nicotine compounds, with 4,4-dichlorodiphenyl sulfide were tested against the armyworm, alder flea beetle, pea aphid, green dock beetle, and California oakworm. This synergistic action has been demonstrated against all insects employed as test subjects in this study.

Compounds chemically similar to 4,4-dichlorodiphenyl sulfide, such as phenyl sulfide (diphenyl thioether) p-tolyl sulfide, 2,5 -xylenyl sulfide, 4,4- dibromophenyl sulfide, and 2,4,4'-tribromophenyl sulfide were employed in synergistic admixture with nicotine, or with nicotine salts or other nicotine compounds.

The relative proportions of active ingredients may vary within wide limits. Thus, for example, the data tabulated above show results obtained using a nicotine-4,4-dichlorodiphenyl sulfide ratio of 1 to 1. In tests against the alder fiea beetle pronounced synergistic action was observed when this ratio was about 2.5 to l.

Synergistic action resulted when the above described aromatic sulfides or substituted aromatic sulfides were employed with nicotine, or with nicotine compounds such as nicotine sulfate, nicotine bentonite, cuprous nicotine cyanide, zinc nicotine thiocyanate, and cupric nicotinamino laurate in the manner stated above.

Insecticidal compositions containing one or more of the aromatic sulfides or substituted aromatic sulfides as the synergist can be combined with solvents, diluents and carrier media, adhesives, spreading, wetting and emulsifying agents and other similar ingredients. They may be advantageously utilized in dusts, sprays, aerosol mixtures, fumigant compositions, insecticidal coating compositions and in general applied by methods commonly used for control or eradication of insects and other pests.

The insecticidal compositions of our invention make it possible to attain the same degree of toxicity With substantially smaller amounts of active ingredients than that required under similar conditions, when analogous compositions are used which do not contain aromatic sulfides or aromatic sulfides substituted with chlorine or bromine, as synergists.

Having thus described our invention, we claim:

1. An insecticidal composition comprising nicotine sulfate and 4,4'-dichlorodiphenyl sulfide in the proportions by weight of about 1 to 2.5 parts of the sulfate to 1 of the sulfide.

2. An insecticidal composition comprising nicotine sulfate and 4,4'-dichlorodiphenyl sulfide as synergist therefor.

CHARLES F. WOODWARD. ELMER L. MAYER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,431,672 Arnold Dec. 2, 1947 2,449,533 McGovran et a1. Sept. 14, 1948 2,459,138 Coflin et a1 Jan. 18, 1949 OTHER REFERENCES Lauger et al., Helv. Chim. Acta., vol. 27, p. 905, June 15, 1944.

Whitecomb, Natl. Shade Tree Conf. Proc. 22, 138-143 (1946), Thru Chem. Abstract, vol. 42, p. 4709 (1948). 

2. AN INSECTICIDAL COMPOSITION COMPRISING NICOTINE SULFATE AND 4,4''-DICHLORODIPHENYL SULFIDE AS SYNERGIST THEREFOR. 